Certain Long-Duration Contracts with Guarantees (Sales Inducements) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($)
Movement in Deferred Sales Inducements [Roll Forward]
Beginning balance	$ 684,844
Capitalization	932
Amortization-Impact of assumption and experience unlocking and true-ups	11,817
Amortization-All other	(144,670)
Change in unrealized investment gains (losses)	(2,802)
Other	(550,121)
Ending balance	$ 0

Change in unrealized investment gains and losses

No definition available.

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Namespace Prefix:	cik777917_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amortization - Impact of assumption and experience unlocking and true-ups

+ References

No definition available.

+ Details

Name:	cik777917_Deferredsalesinducementsamortizationexpenseunlockingandtrueups
Namespace Prefix:	cik777917_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of addition in deferred sales inducement cost.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6481800&loc=d3e11332-158416

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of increase (decrease) in deferred sales inducement cost, classified as other.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of amortization expense (reversal of expense) for deferred sales inducement cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6481800&loc=d3e11332-158416

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6481654&loc=d3e11214-158414

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, after accumulated amortization, of deferred sales inducement cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6481654&loc=d3e11214-158414

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6481800&loc=d3e11332-158416

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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